Compressor-expander having thermal isolation and adjustment features

ABSTRACT

A compressor-expander for use in air conditioning which includes a housing having a chamber of oval profile divided into a compression side and an expansion side and containing a cylindrical rotor having a plurality of outwardly biased vanes forming compartments which progressively decrease and then increase in volume as the rotor rotates. The housing has compression side inlet and outlet ports and expansion side inlet and outlet ports, with the heat exchanger being connected between the compression side outlet port and the expansion side inlet port so that an incoming charge of air is first compressed, flows at constant pressure through the heat exchanger where the heat of compression is removed and then expands in the expansion side to produce a sharp drop in temperature for discharge in the cold state. To improve thermal efficiency, a flexible liner of thin cross section covers the wall of the chamber, a layer of insulation being interposed under the lining to inhibit flow of heat from the compression side to the expansion side. Means are provided for peripherally shifting the liner, if desired, to change the phase of the port positions. In one embodiment, the liner is in the form of a continuous strip supported upon insulated pedestals formed in the wall of the chamber and with diametrically opposed means being provided for applying peripheral shifting movement in opposite directions. In another embodiment, the liner has ends terminating in interdigitated fingers having a limited amount of endwise clearance so that when traction is applied to one of the ends of the liner for adjustment purposes, the effect is to reduce the diametrical dimension of the liner and thus unseat it from the wall of the chamber. When bottoming occurs at the fingers, the liner is bodily shifted to the new position. In a final aspect of the invention, the liner is in the form of a plurality of strips each of which carries a portion of the port openings and with the strips being individually shiftable to vary the relative positions of the ports.

United States Patent [19] Edwards 1 June 3, 1975 1 COMPRESSOR-EXPANDERHAVING THERMAL ISOLATION AND ADJUSTMENT FEATURES [75] Inventor: ThomasC. Edwards, Casselberry,

Fla.

[73] Assignee: The Rovac Corporation, Maitland,

Fla.

[22] Filed: July 29, 1974 21 Appl. No.: 492,885

[52] US. Cl. 62/402; 62/86; 418/13 [51] Int. Cl. F25d 9/00 [58] Field ofSearch 62/402, 86; 418/13 [56] References Cited UNITED STATES PATENTS3,686,893 8/1972 Edwards 62/402 3,752,605 8/1973 Newton 418/13 PrimaryExaminerWilliam J. Wye Attorney, Agent, or Firm-Wolfe, Hubbard, Leydig,Voit & Osann, Ltd.

[5 7] ABSTRACT A compressor-expander for use in air conditioning whichincludes a housing having a chamber of oval profile divided into acompression side and an expansion side and containing a cylindricalrotor having a plurality of outwardly biased vanes forming compartmentswhich progressively decrease and then increase in volume as the rotorrotates. The housing has compression side inlet and outlet ports andexpansion side inlet and outlet ports, with the heat exchanger beingconnected between the compression side outlet port and the expansionside inlet port so that an incoming charge of air is first compressed,flows at constant pressure through the heat exchanger where the heat ofcompression is removed and then expands in the expansion side to producea sharp drop in temperature for discharge in the cold state. To improvethermal efficiency, a flexible liner of thin cross section covers thewall of the chamber, a layer of insulation being interposed under thelining to inhibit flow of heat from the compression side to theexpansion side. Means are provided for peripherally shifting the liner,if desired, to change the phase of the port positions.'1n oneembodiment, the liner is in the form of a continuous strip supportedupon insulated pedestals formed in the wall of the chamber and withdiametrically opposed means being provided for applying peripheralshifting move ment in opposite directions. In another embodiment, theliner has ends terminating in interdigitated fingers having a limitedamount of endwise clearance so that when traction'is applied to one ofthe ends of the liner for adjustment purposes, the effect is to reducethe diametrical dimension of the liner and thus unseat it from the wallof the chamber. When bottoming occurs at the fingers, the liner isbodily shifted to the new position. In a final aspect of the invention,the liner is in the form of a plurality of strips each of which carriesa portion of the port openings and with the strips being individuallyshiftable to vary the relative positions of the ports.

23 Claims, 13 Drawing Figures m'm mima m 3.886; 765 SHEET 3 FHA? 1 COMPRESSOR-EXPANDER HAVING THERMAL ISOLATION AND ADJUSTMENT FEATURES In myprior U.S. Pat. No. 3,686,893, which issued on Aug. 29, 1972, there isdisclosed a compressorexpander having a housing defining a chamber ofoval profile having a Compression side and expansion side in which avaned rotor rotates. Inlet and outlet ports are provided in the housing,with a heat exchanger being connected between the compression sideoutlet port and expansion side inlet port so that a charge of airtrapped between adjacent vanes is (a) compressed, (b) passed through theheat exchanger where the heat of compression is lost and then (c)readmitted to the expansion side where the air expands between adjacentvanes for discharge in the cold state. Because of the unitary nature ofthe device, there is a possible loss in thermal efficiency by leakage ofheat from the hot compression side to the cold expansion side. Moreover,since the inlet and outlet ports are stationarily located, there is acertain rigidity in the operating conditions; for example, the devicecannot be operated with maximum efficiency when there is a sudden changein the temperature of the ambient inlet air. Also, because the deviceworks on the basis of positive displacement, the device as originallydisclosed did not include provision for adjustment to insure that theoutlet air is discharged at substantially ambient pressure.

It is accordingly an object of the present invention to provide acompressor-expander in which a liner of thin flexible material coversthe wall of the chamber, the liner being of limited cross section andbacked up with thermal insulation which may, for example, be air orplastic, to reduce heat flow from the compression side to the expansionside.

It is a further object of the present invention to provide acompressor-expander having a liner having ports formed therein which arein communication with the ports in the housing, but with the linerhaving provision for slight peripheral adjustment in one direction orthe other so as to change the phase position of the ports with respectto the eccentric axes of the chamber thereby to control the operatingcharacteristics. In this connection; it is an object to provide a linerhaving an isolation layer which is made of a material, preferablyteflon, having self-lubricating properties as well as thermal insulationproperties to facilitate shifting movement while providing the desiredthermal isolation.

In one of the aspects of the invention, means are provided for unseatingthe liner from the wall prior to imparting the shifting movement therebyto insure easy shiftability even after long periods of usage.

It is yet another object of the present invention to provide acompressor-expander having a liner formed of a plurality of stripsarranged edge-to-edge, each strip having openings communicating with aportion of the housing ports and with provision for independent stripadjustment thereby to achieve changes in the relative phasing betweenthe ports so as to accommodate the unit to a wide range of operatingconditions.

It is 'a general object of the present invention to provide acompressor-expander having improved thermal isolation between thecompression and expansion sides and having novel provision for portadjustment both ac complishedby the same liner structure, but which isnevertheless of simple construction and which can be manufactured at acost which only slightly exceeds the cost of a compressor-expander unitnot including these features.

Other objects and advantages of the invention will become apparent uponreading the attached description and upon reference to the drawings, inwhich:

FIG. 1 is an elevational view looking along the section line 11 in FIG.2;

FIG. 2 is a broken section taken along the line 22 in FIG. 1 showing oneform of shifting mechanism;

FIG. 3 is a developed view of a portion of the liner looking along theline 33 in FIG. 1;

FIG. 4 is a fragmentary radial section taken along line 44 in FIG. 1;

FIG. 5 shows an alternate form of shifting mechanism;

FIG. 6 is an elevational view showing a modified construction of housingas viewed along line 6-6 in FIG.

FIG. 7 is an end view corresponding to FIG. 6;

FIG. 8 is a fragmentary radial section looking along the line 8--8 inFIG. 6;

FIG. 9 is a developed view of modified form of liner looking along line99 in FIG. 6;

FIG. 10 is an enlarged fragmentary elevation, in partial section,showing one form of adjusting mechanism;

FIG. 1 1 is a view similar to FIG. 9 but showing the interdigitated endsof the liner in bottomed condition;

FIG. 12 is a diagram showing a modified form of adjusting mechanism foruse with the liner of FIG. 9; and,

FIG. 13 is a developed view of a liner consisting of a pair of stripsarranged edge-to-edge and shown somewhat foreshortened.

While the invention has been described in connection with certainpreferred embodiments, it will be understood that I do not intend to belimited to the particular embodiments shown but intend, on the contrary,to cover the various alternative and equivalent constructions includedwithin the spirit and scope of the appended claims.

Turning now to the drawings, there is shown in FIGS. 1 and 2 acompressor-expander having a central chamber 21 which is oval inprofile, the chamber having an outer wall 22. For the sake ofconvenience, the lefthand portion of the housing 20 may be referred toas the compression side C, while the righthand portion may be referredto as the expansion side E. The housing has a compression side inletport 23, a compression side outlet port 24, an expansion side inlet port25 and an expansion side outlet port 26. A heat exchangerdiagrammatically indicated at 27 is connected between the compressionside outlet port 24 and the expansion side inlet port 25. Enclosing thechamber 21 are end plates 31 and 32 which are held securely to themember 20 by means of cap screws 33. The end members include bearings 35and 36.

Journalled in the bearings 35 and 36 is a driven shaft 37 which supportsa rotor 40 having a plurality of radially extending vanes 41-50. Thevanes extend axially from one end plate to the other, and a spring band51 is provided for urging the vanes outwardly toward the wall of thechamber.

As described in my prior patent, the adjacent vanes define compartmentswhich change in volume as the rotor rotates. Thus, a charge of airentering the inlet port 23 and trapped between adjacent vanes 41 and 42is progressively compressed. with the temperature of the air rising byreason of the heat of compression. The

compressed air is discharged from the compression side outlet port 24into the heat exchanger 27 through which the air flows without anysubstantial change in pressure. The same air cooled to nearly ambienttemperature, but still under pressure. is fed to the compression sideinlet port 25 where the charge of air is trapped between adjacent vanesand permitted to expand as the rotation cycle is completed. Theexpansion produces a sudden drop of temperature so that the air in thecold state is discharged from the outlet port 26.

In order to inhibit the heat from the compression side from flowingthrough the housing to warm up the expansion side, with consequentreduction in thermal efficiency, an insulated liner 60 of flexiblematerial and of thin cross section is interposed inside the wall of thechamber as shown in FIG. 1. It will be understood that the liner isprovided with port openings which register with the ports in thehousing. FIG. 3 shows two of the port openings indicated at 63 and 66and which correspond to housing ports 23 and 26. The port openings whichcorrespond to ports 24 and 25 are similar but are not shown. The linermay be made of any durable material, for example, as a ribbon of hardsteel, or a material may be used having self-lubricatingcharacteristics.

In accordance with one of the aspects of the invention, an isolatinglayer of predetermined thickness is interposed between the liner and thewall of the housing, the layer being indicated at 67 in FIGS. 1 and 4.Moreover, the inner wall 22 is grooved axially to define upstandingpedestals 68. The isolating layer is formed of material having goodinsulation properties augmented by the air in the dead air spaces 69.The narrower the pedestals, the less heat will flow and the pedestalsmay be further reduced in area by machining peripheral grooves into theinternal wall 22. If desired, the dead air spaces may comprise the soleinsulating means.

The thin liner with its insulation inhibits heat flow both in the radialdirection and circumferentially. It will be apparent to one skilled inthe art that to further limit the direct heat flow which occurs betweenthe two portions of each of the end plates 31 and 32, the end platesmay, if desired, be equipped with a similar thin thermal liner withoutdeparting from the present invention.

It is one of the features of the invention that means are provided forshifting the liner to change the phase position of the ports withrespect to the eccentric axes, that is the major and minor axes of theellipse. To do this, engaging means are preferably provided on theoutside surface of the liner at diametrically spaced positions, with theengaging means being engaged and operated by a manual shifting meanswhich penetrates the housing. Thus, in the first embodiment of theinvention, in FIGS. 13, the adjustment 70 at the top of the deviceincludes engaging means in the form of rows of perforations orindentations defining teeth and 71 and 72 which are located along thelateral edges of the liner 60. The teeth are engaged by pinions 73 and74, respectively mounted upon a shaft 75 journalled in the housing endmembers, The shafts at the top and bottom of the machine terminate ingear wheels 76 which are meshed with a central gear wheel 77. Shiftingmove ment is applied to the gear system by a manually operated arm 78.When the arm 78 is swung in one direction, the gear wheels 76 rotateequally and in the same direction. Thus, the liner is shifted inopposite directions at the diametrical points. Because of the spacedapplication of shifting pressure at diametrical points and because ofthe location of the engaging teeth 71 and 72 along the lateral edges ofthe liner, binding or cocking are avoided and only balanced forces areapplied.

In carrying out the invention, a material is chosen for the isolatinglayer 67 which not only has insulating properties but which hasself-lubricating properties as well, so that only light adjusting forcesare required. The material which I prefer to use to achieve the combinedinsulating and lubricating functions is teflon, but it will be apparentto one skilled in the art that other materials, notably other plastics,may be substituted, having approximately the same insulation andlubrication features, materials either presently available on the marketor which may be subsequently introduced.

In lieu of the gears 76 and 77, the upper and lower shafts may becoupled together by pulleys 81 and 82 about which is trained a belt 83(FIG. 5). To preserve the phase position, the belt may be of the toothedtype referred to in the art as a timing or cog belt.

In accordance with a further feature of the invention, the liner,instead of being endless as disclosed in FIG. 1, is formed of a thindouble-ended strip, with the ends thereof being shaped into fingerswhich are interdigitated together and with a small amount of peripheralclearance at the tips of the fingers. The interdigitation and peripheralclearance, combined with slight outward springing of the strip, enablesthe strip to be easily inserted into position, following which the stripexpands into its seated position against the wall of the chamber.Unseating of the strip for maintenance or positional adjustment iseasily accomplished by reversing the procedure, that is by contractingthe strip.

Further, means are provided for applying traction selectively to theends of the liner so that the liner is effectively shortened as theclearance is taken up, reducing the diametrical dimension of the linerand causing it to be unseated from the wall of the housing, followingwhich continued traction results in bodily shifting of the liner to anew phase position. Thus, referring to FIG. 6 where correspondingelements are indicated, where possible, by the same reference numeralplus a, there is shown a housing 200 defining a central space 21abounded by a wall 22a of oval profile. The ports are indicated at23a-26a and the heat exchanger at 27a. The liner 60a of FIG. 9 has afull complement of port openings, but only the port openings 63a and 66awhich communicate with ports 23a and 26a in the housing are shown. Justas in the first embodiment, an isolating layer 67a of teflon or the likeis interposed between the liner and the housing and the housing is,moreover, internally machined to define axially extending pedestals 68awhich are bounded by dead air spaces 69a to provide an effective barrieragainst the radial flow of heat either into the housing on thecompression side or from the housing on the expansion side. One end ofthe liner is formed with fingers 91 while the other end is formed withfingers 92 which are closely interfitted in the axial direction butwhich provide peripheral clearance as indicated at 93. For the purposeof providing traction to the fingers 91, abutments 94 are provided,while the other set of fingers 92 have similar abutments'95. Forapplying traction alternately to the two sets of abutments, a unitaryadjusting member is used, engaged by a captive screw 101 (FIG. 10)

and having a pointer 102 cooperating with a scale 103.

When it is desired to move the liner clockwise, the unitary adjustingmember 100 is moved to the right as shown in FIG. 11 into engagementwith abutments 95 on the fingers 71a. The initial portion of themovement takes up the clearance indicated at 93 so that the size of theloop of liner is slightly reduced, breaking the liner temporarily awayfrom its supporting surfaces. Continued movement of the adjusting member100 after bottoming takes place causes the liner to be bodily shifted inthe clockwise direction. After the liner has achieved its new position,the adjusting member 100 may be backed off to permit the liner toachieve its original seated condition. Movement of the adjusting memberto the left results, similarly, to shifting of the liner in thecounterclockwise direction.

An alternative form of shifting mechanism is diagrammaticallyillustrated in FIG. 12. In this figure, the adjusting member indicatedat 100a may be in the form of a butterfly plate centrally pivoted at101a and engageable by a wrench or similar tool to first reduce thedimension of the liner and then, by continued movement, produce bodilyshifting. The version of adjusting device shown in FIG. 12 has theadvantage that the phase position of the liner is at all timesaccurately indi cated by a pointer 102a which is located at thelowermost position of the liner and which cooperates with a scaleindicated at 103a. If desired, a similar member 100a cooperating withsimilar abutments may be provided in the lower position for simultaneousactuation.

In the embodiments described above, all of the port openings in theliner are changed in phase with respect to the eccentric axes to thesame degree. However, in accordance with the invention, the liner may beformed not of a single strip of flexible material but of a plurality ofstrips of the same thickness and arranged closely side by side to spanthe distance between the end plates, and with a portion of the portopenings being provided in one of the liner strips and a portion of theport openings in the other. For example, the liner may be formed, asshown in developed form in FIG. 13, as two separate strips arranged sideby side and which are indicated at 60b and 60c. The first strip 60bcarries the port openings 63b and 66b (corresponding to the housingports 23 and 26), while the second strip carries the port openings 64band 65b (corresponding to ports 24 and 25). It will be understood thateach of the strips is provided with separate adjusting means of the typeshown in FIGS. or 12. Alternatively, only one of the strips may bemovable and the other may be relatively fixed to the housing.

The provision of a portion of the port openings in one strip and aportion in another enables a high degree of design versatility since theport openings may be provided in the strips in any desirable orconceivable combination. Moreover, since it is a simple matter to removethe strips by loosening one of the end plates, strips of specificallydifferent porting may be readily substituted to adapt the same basicstructure to widely different operating conditions.

As will be appreciated by one skilled in the art, the shifting of theports permitted by the present invention enables the user of themachine, for example, to compensate for different temperatures ofambient air. By shifting of the outlet port opening 661), the dischargedair may be caused to have the same pressure, at point of discharge, asthe ambient air, thereby minimizing noise level. The shifting of portsmay be also employed inter alia to control the thermal load (temperatureor discharge) and to compensate for changes in driving speed.

While the invention has been described in connection with acompressor-expander having vanes which are radially slideable in therotor, such structure has been to simplify understanding of theinvention, and it will be understood that the invention is by no meanslimited to use of sliding vanes but is fully applicable to use withtilting vanes as covered in my application Ser. No. 492,608, filed July29, 1974.

In the above embodiments, the invention has been applied to an endlessliner and one which is jointed in the top position. It will beunderstood that my invention is not limited to this and that Icontemplate that a liner may be provided consisting of two sectionsjointed by interdigitation both top and bottom. In such event, anadjusting means such as that set forth in FIGS. 10 and 12 would be usedin both the top and bottom positions. Such an arrangement would have theadvantage of differential port adjustment on the compression andexpansion sides while preserving full-width port openings for minimumthrottling of air. Any desired means may, of course, be employed toclamp a liner section in fixed position once it has been adjusted.

The term interdigitated as used herein refers to any overlapped andinterfitted joint providing relative peripheral movement plus smoothvane transition. While flow through the heat exchanger has been referredto as being at constant pressure, it will be understood that minorpressure variations may occur in the heat exchanger without departingfrom the present invention. Also while the material for thermallyisolating the liner may take the form of plastic having lubricatingproperties, as discussed, it will be apparent that many other stable,poorly conducting solids may be employed, as for example carbon. Theterm oval as used herein is directed toward a chamber having a smoothlycontinuous outer wall and is not limited to any particular degree ofelliptical eccentricity; on the contrary, the eccentricity may approachunity without departing from the present invention.

What I claim is:

1. In a compressor-expander for use in air conditioning, the combinationcomprising a housing defining a chamber having an outer wall of ovalprofile having a compression side and an expansion side and enclosed byend plates, a cylindrical rotor extending between the end plates andhaving a shaft journalled therein, means defining compression side inletand outlet ports as well as expansion side inlet and outlet ports, aheat exchanger interposed between the compression side outlet port andthe expansion side inlet port, the rotor having a plurality of radiallymovable and outwardly biased vanes extending into engagement with theend plates, a liner in the form of a flexible strip of oval profilecovering the outer wall and having port openings in respectivecommunication with the ports in the housing so that a charge of airdrawn in between adjacent vanes at the compression side inlet port whenthe rotor is rotated: (a) is compressed with increase in temperature dueto heat of compression, (b) flows at substantially constant pressurethrough the heat exchanger where heat of compression is absorbed andthen (c) expands in the expansion side toproduce a sharp drop intemperature for discharge in the cold state through the expansion sideoutlet port, the liner being of thin cross section for limited heatconductivity and having a layer of insulation between it and the outerwall for preventing flow of heat through the housing from thecompression side to the expansion side.

2. The combination as claimed in claim 1 in which the outer wall of thechamber is formed with pedestals of limited cross section for suportingthe liner in oval configuration, the spaces between the pedestals beingoccupied by insulation.

3. The combination as claimed in claim 2 in which the insulatingmaterial between the pedestals is air.

4. The combination as claimed in claim 2 in which each of the pedestalsis topped with a thin layer of insulation of predetermined thickness.

5. In a compressor-expander for use in air conditioning, the combinationcomprising a housing defining a chamber having an outer wall of ovalprofile divided into a compression side and an expansion side andenclosed by end plates, a cylindrical rotor extending between the endplates and having a shaft journalled therein, means defining compressionside inlet and outlet ports as well as expansion side inlet and outletports, a heat exchanger interposed between the compression side outletport and the expansion side inlet port, the rotor having a plurality ofoutwardly biased vanes extending into engagement with the end plates, aliner in the form of a flexible strip of oval profile covering the outerwall and having port openings in respective communication with the portsin the housing so that a charge of air drawn in between adjacent vanesat the compression side inlet port when the rotor is rotated: (a) iscompressed with increase in temperature due to the heat of compression,(b) flows at substantially constant pressure through the heat exchangerwhere heat of the compression is removed and then (c) expands in theexpansion side to produce a sharp drop in temperature for discharge inthe cold state through the expansion side outlet port, the liner havingexternally accessible means for shifting the same peripherally inopposite directions by a slight amount thereby to change the effectivephase positions of the ports.

6. The combination as claimed in claim 5 in which the shifting meansincludes teeth on the outside surface of the liner and a manuallyoperated gear for meshing with the teeth for shifting of the liner inopposite directions.

7. The combination as claimed in claim 5 in which teeth are provided onthe outside surface of the liner at substantially diametrical positions,a pair of gears respectively meshing with the teeth, and means forcoupling the gears together.

8. The combination as claimed in claim 5 in which the liner is providedwith a first set of teeth at a position between the compression sideinlet port and the expansion side outlet port and a second set of teethbetween the compression side outlet port and the expansion side inletport, a pair of gears for respectively meshing with the sets of teeth,and means for rotating the gears for imparting equal amounts ofperipheral displacement to the liner.

9. The combination as claimed in claim 5 in which first and second setsof teeth are provided on the outer surface of the liner adjacentrespective edges of the liner and in which the externally accessibleshifting means is in the form of a shaft journalled in the housing andpositioned along side of the liner, the shaft having gears respectivelyaligned with the sets of teeth for shifting the liner peripherally inopposite directions free of generation of any unbalanced cocking forces.

10. The combination as claimed in claim 5 in which the liner is in theform of an endless loop having engagement means on the outside of theliner at diametrically spaced positions and first and second shiftingmeans penetrating the housing and coupled to the engagement means forimparting equal amounts of shifting movement to the liner.

11. In a compressor-expander for use in air conditioning, thecombination comprising a housing defining a chamber having an outer wallof oval profile divided into a compression side and an expansion sideand enclosed by end plates, a cylindrical rotor extending between theend plates and having a shaft journalled therein, means definingcompression side inlet and outlet ports as well as expansion side inletand outlet ports, a heat exchanger interposed between the compressionside outlet port and the expansion side inlet port, the rotor having aplurality of outwardly biased vanes extending into engagement with theend plates to form compartments which are progressively decreased andthen increased in volume as the rotor rotates, a liner in the form of astrip of oval profile covering the outer wall of the chamber and havingport openings in respective communication with the ports in the housingso that a charge of air drawn in between adjacent vanes at thecompression side inlet port (a) is compressed with increase intemperature due to heat of compression, (b) flows at substantiallyconstant pressure through the heat exchanger where the heat ofcompression is removed and then (c) expands in the expansion side toproduce a sharp drop in temperature for discharge in the cold statethrough the expansion side outlet port, the liner being of thin crosssection for limited heat conductivity and having an isolation layer ofpredetermined thickness between the liner and the wall, the isolationlayer being made of a material having good thermal insulating propertiesfor preventing flow of heat through the housing from the compressionside to the expansion side as well as having self-lubricatingproperties, the liner in addition having externally accessible means formanually shifting the same peripherally in opposite directions by aslight amount thereby to change the effective phase position of theports.

12. The combination as claimed in claim 11 in which the isolating layeris formed of teflon.

13. The combination as claimed in claim 11 in which the outer wall ofthe chamber is undercut to provide peripherally spaced pedestals, eachof the pedestals being capped by an isolating layer of predeterminedthickness formed of a material which combines thermal insulation withself-lubricating properties to facilitate the peripheral shifting of theliner.

14. In a compressor-expander for use in air conditioning, thecombination comprising a housing defining a chamber having an outer wallof oval profile divided into a compression side and an expansion sideand enclosed by end plates, a cylindrical rotor extending between theend plates and having a shaft journalled therein, means in the housingdefining compression side inlet and outlet ports, as well as expansionside inlet and outlet ports, a heat exchanger interposed between thecompression side outlet port and expansion side inlet port, the rotorhaving a plurality of outwardly biased vanes extending into engagementwith the end plates to form compartments which are progressivelydecreased and then increased in volume as the. rotor rotates, a liner inthe form of a flexible strip. of oval profile covering theouter wall andhaving port openings in respective communication with the ports in thehousing so. that a charge of air drawn in between adjacent vanes at thecompression side inlet port (a) is compressed with increase intemperature due to heat of compression, (b) flows at substantiallyconstant pressure through the heat exchanger where the heat ofcompression is removed and then (c) expands in the expansion side toproduce a sharp drop in temperature for discharge in the cold statethrough the expansion side outlet port, means for bodily shifting theliner peripherally in opposite directions by a slight amount thereby tochange the effective phase position of the ports, the liner being formedof a thin strip of metal having interdigitated ends which are fittedtogether to provide a joint having smooth transition with sufficientperipheral clearance and sufficient outward springing to insure seatingof the liner on the wall.

15. In a compressor-expander for use in air conditioning. thecombination comprising a housing defining a chamber having an outer wallof oval profile divided into a compression side and an expansion sideand enclosed by end plates, a cylindrical rotor extending between theend plates and having a shaft journalled therein, means in the housingdefining compression side inlet and outlet ports, as well as expansionside inlet and outlet ports, a heat exchanger interposed between thecompression side outlet port and expansion side inlet port, the rotorhaving a plurality of outwardly biased vanes extending into engagementwith the end plates to form compartments which are progressivelydecreased and then increased in volume as the rotor rotates, a liner inthe form of a flexible strip of oval profile covering the outer wall andhaving port openings in respective communication with the ports in thehousing so that a charge of air drawn in between adjacent vanes at thecompression side inlet port (a) is compressed with increase intemperature due to heat of compression, (b) flows at substantiallyconstant pressure through the heat exchanger where heat of compressionis removed and then (c) expands in the expansion side to produce a sharpdrop in temperature for discharge in the cold state through theexpansion side outlet port, means for bodily shifting the linerperipherally in opposite directions by a slight amount thereby to changethe effective phase position of the ports, the liner being formed of astraight strip of flexible material having interdigitated ends which arefitted together and which have end-to-end clearance with means forrelatively moving the ends toward one another to slightly reduce thelength, hence the diametrical dimension, so that the liner is liftedfree of the wall of the chamber to facilitate the shifting movement.

16. The combination as claimed in claim in which a layer of lubricatingmaterial is interposed between the liner and the wall for the purpose oflubricating the shifting movement at those portions of the liner whichremain in contact with the wall.

17. The combination as claimed in claim 15 in which the ends of theliner are formed into interdigitated fingers which are fitted togetherwith end-to-end clearance, the fingers having abutments adjacent thetips thereof, and means for engaging associated abutments to produce areduction in the end-to-end clearance with consequent reduction in thediametrical dimension so that the liner is lifted free of the wallfollowed by shifting movement thereof to a new position.

18. The combination as claimed in claim 15 in which the ends of theliner are formed into interdigitated fingers having first and second setof abutments at the respective tips thereof and providing limitedend-to-end clearance, and an adjusting member penetrating the housingfor alternatively engaging one of the sets of abutments to applypressure thereto in the peripheral direction for (a) taking up theend-to-end clearance thereby to reduce the diametrical dimension so thatthe liner is lifted free of the wall accompanied by interdigitatedbottoming of the fingers, and (b) upon continued movement effectingbodily shifting of the liner to a new position for adjustment of thephase position of the ports, following which the adjusting means isbacked off to restore seated contact between the liner and the wall.

19. The combination as claimed in claim 15 in which the first and secondends of the liner have fingers which are interdigitated and lie closelyside by side with limited clearance at the ends of the fingers and inwhich means are provided for alternatively applying traction to therespective ends of the liner with the result that the end clearance istaken up for slightly reducing the diametrical dimension of a linerthereby to lift it clear of the wall followed by bodily shifting of theliner to a new phase position.

20. The combination as claimed in claim 15 in which abutments areprovided on the respective ends of the liner for applying tractionthereto and in which a unitary adjusting member is provided having meansfor imparting shifting movement in opposite directions for alternativelyengaging the abutments for unseating the liner from the wall of thehousing and for subsequently imparting bodily shifting movement to theliner for adjusting the same to a new phase position.

21. In a compressor-expander for use in air conditioning, thecombination comprising a housing defining a chamber having an outer wallof oval profile divided into a compression side and an expansion side,and enclosed by end plates, a cylindrical'rotor extending between theend plates and having a shaft journalled therein, means in the housingdefining a compression side inlet port, compression side outlet port,expansion side inlet port, and expansion si'de outlet port, a heatexchanger interposed between the compression side outlet port and theexpansion side inlet port, the rotor having a plurality of vanesextending into engagement with the end plates and outwardly biased sothat adjacent vanes define compartments which are progressivelydecreased and then increased in volume as the rotor rotates, a liner inthe form of a plurality of thin flexible strips of oval profile mergingsmoothly edge to edge and extending between the end plates, the stripseach having port openings communicating with a portion of the ports inthe housing and at least a portion of the strips being peripherallyadjustable to vary the relative phase positions of the ports.

22. In a compressor-expander for use in air conditioning, thecombination comprising a housing defining a chamber having an outer wallof oval profile divided into a compression side and an expansion sideand enclosed by end plates, a cylindrical rotor extending between theend plates and having a shaft journalled therein, means in the housingdefining a compression ing smoothly edge to edge for covering the outerwall, the strips each having port openings communicating with a portionof the ports in the housing and at least one of the strips beingperipherally adjustable to vary the relative phase positions of theports.

23. The combination as claimed in claim 22 in which both of the stripsare peripherally shiftable and provided with position adjusting means.

1. In a compressor-expander for use in air conditioning, the combinationcomprising a housing defining a chamber having an outer wall of ovalprofile having a compression side and an expansion side and enclosed byend plates, a cylindrical rotor extending between the end plates andhaving a shaft journalled therein, means defining compression side inletand outlet ports as well as expansion side inlet and outlet ports, aheat exchanger interposed between the compression side outlet port andthe expansion side inlet port, the rotor having a plurality of radiallymovable and outwardly biased vanes extending into engagement with theend plates, a liner in the form of a flexible strip of oval profilecovering the outer wall and having port openings in respectivecommunication with the ports in the housing so that a charge of airdrawn in between adjacent vanes at the compression side inlet port whenthe rotor is rotated: (a) is compressed with increase in temperature dueto heat of compression, (b) flows at substantially constant pressurethrough the heat exchanger where heat of compression is absorbed andthen (c) expands in the expansion side to produce a sharp drop intemperature for discharge in the cold state through the expansion sideoutlet port, the liner being of thin cross section for limited heatconductivity and having a layer of insulation between it and the outerwall for preventing flow of heat through the housing from thecompression side to the expansion side.
 1. In a compressor-expander foruse in air conditioning, the combination comprising a housing defining achamber having an outer wall of oval profile having a compression sideand an expansion side and enclosed by end plates, a cylindrical rotorextending between the end plates and having a shaft journalled therein,means defining compression side inlet and outlet ports as well asexpansion side inlet and outlet ports, a heat exchanger interposedbetween the compression side outlet port and the expansion side inletport, the rotor having a plurality of radially movable and outwardlybiased vanes extending into engagement with the end plates, a liner inthe form of a flexible strip of oval profile covering the outer wall andhaving port openings in respective communication with the ports in thehousing so that a charge of air drawn in between adjacent vanes at thecompression side inlet port when the rotor is rotated: (a) is compressedwith increase in temperature due to heat of compression, (b) flows atsubstantially constant pressure through the heat exchanger where heat ofcompression is absorbed and then (c) expands in the expansion side toproduce a sharp drop in temperature for discharge in the cold statethrough the expansion side outlet port, the liner being of thin crosssection for limited heat conductivity and having a layer of insulationbetween it and the outer wall for preventing flow of heat through thehousing from the compression side to the expansion side.
 2. Thecombination as claimed in claim 1 in which the outer wall of the chambeRis formed with pedestals of limited cross section for suporting theliner in oval configuration, the spaces between the pedestals beingoccupied by insulation.
 3. The combination as claimed in claim 2 inwhich the insulating material between the pedestals is air.
 4. Thecombination as claimed in claim 2 in which each of the pedestals istopped with a thin layer of insulation of predetermined thickness.
 5. Ina compressor-expander for use in air conditioning, the combinationcomprising a housing defining a chamber having an outer wall of ovalprofile divided into a compression side and an expansion side andenclosed by end plates, a cylindrical rotor extending between the endplates and having a shaft journalled therein, means defining compressionside inlet and outlet ports as well as expansion side inlet and outletports, a heat exchanger interposed between the compression side outletport and the expansion side inlet port, the rotor having a plurality ofoutwardly biased vanes extending into engagement with the end plates, aliner in the form of a flexible strip of oval profile covering the outerwall and having port openings in respective communication with the portsin the housing so that a charge of air drawn in between adjacent vanesat the compression side inlet port when the rotor is rotated: (a) iscompressed with increase in temperature due to the heat of compression,(b) flows at substantially constant pressure through the heat exchangerwhere heat of the compression is removed and then (c) expands in theexpansion side to produce a sharp drop in temperature for discharge inthe cold state through the expansion side outlet port, the liner havingexternally accessible means for shifting the same peripherally inopposite directions by a slight amount thereby to change the effectivephase positions of the ports.
 6. The combination as claimed in claim 5in which the shifting means includes teeth on the outside surface of theliner and a manually operated gear for meshing with the teeth forshifting of the liner in opposite directions.
 7. The combination asclaimed in claim 5 in which teeth are provided on the outside surface ofthe liner at substantially diametrical positions, a pair of gearsrespectively meshing with the teeth, and means for coupling the gearstogether.
 8. The combination as claimed in claim 5 in which the liner isprovided with a first set of teeth at a position between the compressionside inlet port and the expansion side outlet port and a second set ofteeth between the compression side outlet port and the expansion sideinlet port, a pair of gears for respectively meshing with the sets ofteeth, and means for rotating the gears for imparting equal amounts ofperipheral displacement to the liner.
 9. The combination as claimed inclaim 5 in which first and second sets of teeth are provided on theouter surface of the liner adjacent respective edges of the liner and inwhich the externally accessible shifting means is in the form of a shaftjournalled in the housing and positioned along side of the liner, theshaft having gears respectively aligned with the sets of teeth forshifting the liner peripherally in opposite directions free ofgeneration of any unbalanced cocking forces.
 10. The combination asclaimed in claim 5 in which the liner is in the form of an endless loophaving engagement means on the outside of the liner at diametricallyspaced positions and first and second shifting means penetrating thehousing and coupled to the engagement means for imparting equal amountsof shifting movement to the liner.
 11. In a compressor-expander for usein air conditioning, the combination comprising a housing defining achamber having an outer wall of oval profile divided into a compressionside and an expansion side and enclosed by end plates, a cylindricalrotor extending between the end plates and having a shaft journalledtherein, means defining compression side inlet and outlet ports as wellas expansion side inlet and outlEt ports, a heat exchanger interposedbetween the compression side outlet port and the expansion side inletport, the rotor having a plurality of outwardly biased vanes extendinginto engagement with the end plates to form compartments which areprogressively decreased and then increased in volume as the rotorrotates, a liner in the form of a strip of oval profile covering theouter wall of the chamber and having port openings in respectivecommunication with the ports in the housing so that a charge of airdrawn in between adjacent vanes at the compression side inlet port (a)is compressed with increase in temperature due to heat of compression,(b) flows at substantially constant pressure through the heat exchangerwhere the heat of compression is removed and then (c) expands in theexpansion side to produce a sharp drop in temperature for discharge inthe cold state through the expansion side outlet port, the liner beingof thin cross section for limited heat conductivity and having anisolation layer of predetermined thickness between the liner and thewall, the isolation layer being made of a material having good thermalinsulating properties for preventing flow of heat through the housingfrom the compression side to the expansion side as well as havingself-lubricating properties, the liner in addition having externallyaccessible means for manually shifting the same peripherally in oppositedirections by a slight amount thereby to change the effective phaseposition of the ports.
 12. The combination as claimed in claim 11 inwhich the isolating layer is formed of teflon.
 13. The combination asclaimed in claim 11 in which the outer wall of the chamber is undercutto provide peripherally spaced pedestals, each of the pedestals beingcapped by an isolating layer of predetermined thickness formed of amaterial which combines thermal insulation with self-lubricatingproperties to facilitate the peripheral shifting of the liner.
 14. In acompressor-expander for use in air conditioning, the combinationcomprising a housing defining a chamber having an outer wall of ovalprofile divided into a compression side and an expansion side andenclosed by end plates, a cylindrical rotor extending between the endplates and having a shaft journalled therein, means in the housingdefining compression side inlet and outlet ports, as well as expansionside inlet and outlet ports, a heat exchanger interposed between thecompression side outlet port and expansion side inlet port, the rotorhaving a plurality of outwardly biased vanes extending into engagementwith the end plates to form compartments which are progressivelydecreased and then increased in volume as the rotor rotates, a liner inthe form of a flexible strip of oval profile covering the outer wall andhaving port openings in respective communication with the ports in thehousing so that a charge of air drawn in between adjacent vanes at thecompression side inlet port (a) is compressed with increase intemperature due to heat of compression, (b) flows at substantiallyconstant pressure through the heat exchanger where the heat ofcompression is removed and then (c) expands in the expansion side toproduce a sharp drop in temperature for discharge in the cold statethrough the expansion side outlet port, means for bodily shifting theliner peripherally in opposite directions by a slight amount thereby tochange the effective phase position of the ports, the liner being formedof a thin strip of metal having interdigitated ends which are fittedtogether to provide a joint having smooth transition with sufficientperipheral clearance and sufficient outward springing to insure seatingof the liner on the wall.
 15. In a compressor-expander for use in airconditioning, the combination comprising a housing defining a chamberhaving an outer wall of oval profile divided into a compression side andan expansion side and enclosed by end plates, a cylindrical rotorextending between the end plates and having a shaft journAlled therein,means in the housing defining compression side inlet and outlet ports,as well as expansion side inlet and outlet ports, a heat exchangerinterposed between the compression side outlet port and expansion sideinlet port, the rotor having a plurality of outwardly biased vanesextending into engagement with the end plates to form compartments whichare progressively decreased and then increased in volume as the rotorrotates, a liner in the form of a flexible strip of oval profilecovering the outer wall and having port openings in respectivecommunication with the ports in the housing so that a charge of airdrawn in between adjacent vanes at the compression side inlet port (a)is compressed with increase in temperature due to heat of compression,(b) flows at substantially constant pressure through the heat exchangerwhere heat of compression is removed and then (c) expands in theexpansion side to produce a sharp drop in temperature for discharge inthe cold state through the expansion side outlet port, means for bodilyshifting the liner peripherally in opposite directions by a slightamount thereby to change the effective phase position of the ports, theliner being formed of a straight strip of flexible material havinginterdigitated ends which are fitted together and which have end-to-endclearance with means for relatively moving the ends toward one anotherto slightly reduce the length, hence the diametrical dimension, so thatthe liner is lifted free of the wall of the chamber to facilitate theshifting movement.
 16. The combination as claimed in claim 15 in which alayer of lubricating material is interposed between the liner and thewall for the purpose of lubricating the shifting movement at thoseportions of the liner which remain in contact with the wall.
 17. Thecombination as claimed in claim 15 in which the ends of the liner areformed into interdigitated fingers which are fitted together withend-to-end clearance, the fingers having abutments adjacent the tipsthereof, and means for engaging associated abutments to produce areduction in the end-to-end clearance with consequent reduction in thediametrical dimension so that the liner is lifted free of the wallfollowed by shifting movement thereof to a new position.
 18. Thecombination as claimed in claim 15 in which the ends of the liner areformed into interdigitated fingers having first and second set ofabutments at the respective tips thereof and providing limitedend-to-end clearance, and an adjusting member penetrating the housingfor alternatively engaging one of the sets of abutments to applypressure thereto in the peripheral direction for (a) taking up theend-to-end clearance thereby to reduce the diametrical dimension so thatthe liner is lifted free of the wall accompanied by interdigitatedbottoming of the fingers, and (b) upon continued movement effectingbodily shifting of the liner to a new position for adjustment of thephase position of the ports, following which the adjusting means isbacked off to restore seated contact between the liner and the wall. 19.The combination as claimed in claim 15 in which the first and secondends of the liner have fingers which are interdigitated and lie closelyside by side with limited clearance at the ends of the fingers and inwhich means are provided for alternatively applying traction to therespective ends of the liner with the result that the end clearance istaken up for slightly reducing the diametrical dimension of a linerthereby to lift it clear of the wall followed by bodily shifting of theliner to a new phase position.
 20. The combination as claimed in claim15 in which abutments are provided on the respective ends of the linerfor applying traction thereto and in which a unitary adjusting member isprovided having means for imparting shifting movement in oppositedirections for alternatively engaging the abutments for unseating theliner from the wall of the housing and for subsequently imparting bodilyshifting movEment to the liner for adjusting the same to a new phaseposition.
 21. In a compressor-expander for use in air conditioning, thecombination comprising a housing defining a chamber having an outer wallof oval profile divided into a compression side and an expansion side,and enclosed by end plates, a cylindrical rotor extending between theend plates and having a shaft journalled therein, means in the housingdefining a compression side inlet port, compression side outlet port,expansion side inlet port, and expansion side outlet port, a heatexchanger interposed between the compression side outlet port and theexpansion side inlet port, the rotor having a plurality of vanesextending into engagement with the end plates and outwardly biased sothat adjacent vanes define compartments which are progressivelydecreased and then increased in volume as the rotor rotates, a liner inthe form of a plurality of thin flexible strips of oval profile mergingsmoothly edge to edge and extending between the end plates, the stripseach having port openings communicating with a portion of the ports inthe housing and at least a portion of the strips being peripherallyadjustable to vary the relative phase positions of the ports.
 22. In acompressor-expander for use in air conditioning, the combinationcomprising a housing defining a chamber having an outer wall of ovalprofile divided into a compression side and an expansion side andenclosed by end plates, a cylindrical rotor extending between the endplates and having a shaft journalled therein, means in the housingdefining a compression side inlet port, compression side outlet port,expansion side inlet port, and expansion side outlet port, a heatexchanger interposed between the compression side outlet port and theexpansion side inlet port, the rotor having a plurality of vanesextending into engagement with the end plates and outwardly biased toform compartments which are progessively decreased and then increased involume as the rotor rotates, a liner in the form of a pair of thinflexible strips of oval profile merging smoothly edge to edge forcovering the outer wall, the strips each having port openingscommunicating with a portion of the ports in the housing and at leastone of the strips being peripherally adjustable to vary the relativephase positions of the ports.